15.1.15.
A cargo of 1 mass m1 = 2 kg drives a roller 2 of mass m2 = 1 kg. Coefficient
Friction rolling? = 0.01 m. Determine the work of the external forces of the system when the load is lowered to
Height h = 1m, if the radius of the roller is R = 0.1 m. (Answer 18.6)